1. Field of the Invention
The present invention relates to a method of ocular assessment to determine on an essentially real time basis certain physical conditions in the body and to apparatus for effecting such monitoring.
2. Description of the Prior Art
It has long been known to examine the eye to determine certain characteristics of the eye, such as near and far vision in order to ascertain whether an individual might need to wear corrective lenses in the form of eyeglasses or contact lenses, for example.
It has also been known to monitor the eye to determine other physical characteristics of the eye, such as the shape of the cornea. See, for example, U.S. Pat. Nos. 4,995,716 and 5,159,361.
U.S. Pat. No. 4,995,716 discloses apparatus for measuring the topography of a cornea. Light projection means projects a grid pattern on the eye which is coated with a substance capable of making the eye non-transparent. An electronic camera is provided in a second pathway in line with the eye for obtaining and producing an image of the grid pattern projected onto the eye. One arm of the apparatus carries the light projection means and the grid means on one side of the centerline and the camera means on the other side. Processing means are connected to the camera for obtaining data from the image of the grid pattern projected onto the eye thereby producing quantitative and qualitative analysis of the contour of the cornea. See, also, U.S. Pat. No. 5,159,361.
In summary, it has been known to provide apparatus to which non-contacting optical and electronic apparatus can make certain determinations about the eye itself as well as other conditions in the body as a result of changes in the eye.
In spite of the foregoing, there remains a real and substantial need for a method and associated apparatus for effecting automated determinations regarding certain specific conditions in the body based upon examination of the eye.
The present invention has met the above-described needs.
The present invention has provided a method of monitoring a medical condition in a subject. The method includes impinging light on to the subject""s eye and directing the reflected light from the impinging light beam to a photosensor with subsequent conversion in the photosensor of the reflected light into corresponding electrical signals. The electrical signals are delivered to a processor, which may be a computer, which contains stored information regarding desired parameters of the particular medical condition. A comparison is effected between the photosensor delivered electrical signal containing the data and the stored data to determine if an undesirable medical condition exists and, if such an undesirable medical condition exists, communicating such event. The process is repeated cyclically. Among the specific conditions that may be monitored are miosis, carbon monoxide and other toxin levels in the body, and blood flow characteristics, for example.
The apparatus for monitoring a medical condition may have a light source directing light onto at least one eye of the subject with sensor means for receiving the reflected light and converting light into corresponding electrical signals. Processor means receive the electrical signals and compare the same with stored information regarding desired parameters of the medical condition and emits the result of the comparison. The processor has controls for cyclically repeating the monitoring at desired predetermined intervals.
It is an object of the present invention to provide an efficient and accurate means of employing information obtained from the eye to determine whether certain changes in the physical condition of an individual have occurred.
It is a further object of the present invention to effect such determinations rapidly in minimum time.
It is yet another object of the present invention to provide apparatus for making such determinations in vehicles, customized head mounted apparel at workstations and other ways which facilitate ongoing monitoring of the eye without interfering meaningfully with activities of the individual being monitored.
It is yet a further object of the present invention to provide such a method and apparatus which employs computerized processing through comparison of the data obtained from observations of the eye with either prior data obtained from the same individual or standardized data regarding normal and/or abnormal conditions in the body.
It is another object of the invention to provide an automated system for continuous or intermittent monitoring of some optically apparent characteristic that corresponds to an undesirable metabolic state or to a toxic exposure.
It is yet another object of the present invention to provide a system which serves as an early warning or generalized information leading to subsequent medical analysis.
It is yet another object of the invention to provide such a system which permits frequent monitoring of certain medical conditions as determined from external observation of the eye in order to minimize safety and health risks.
These and other objects of the invention will be more fully understood from the following description of the invention with reference to the drawings appended hereto.